mirror of
https://github.com/python/cpython.git
synced 2025-11-04 07:31:38 +00:00
283 lines
8.1 KiB
Python
283 lines
8.1 KiB
Python
import types
|
|
import unittest
|
|
|
|
|
|
class Test(unittest.TestCase):
|
|
def test_init_subclass(self):
|
|
class A:
|
|
initialized = False
|
|
|
|
def __init_subclass__(cls):
|
|
super().__init_subclass__()
|
|
cls.initialized = True
|
|
|
|
class B(A):
|
|
pass
|
|
|
|
self.assertFalse(A.initialized)
|
|
self.assertTrue(B.initialized)
|
|
|
|
def test_init_subclass_dict(self):
|
|
class A(dict):
|
|
initialized = False
|
|
|
|
def __init_subclass__(cls):
|
|
super().__init_subclass__()
|
|
cls.initialized = True
|
|
|
|
class B(A):
|
|
pass
|
|
|
|
self.assertFalse(A.initialized)
|
|
self.assertTrue(B.initialized)
|
|
|
|
def test_init_subclass_kwargs(self):
|
|
class A:
|
|
def __init_subclass__(cls, **kwargs):
|
|
cls.kwargs = kwargs
|
|
|
|
class B(A, x=3):
|
|
pass
|
|
|
|
self.assertEqual(B.kwargs, dict(x=3))
|
|
|
|
def test_init_subclass_error(self):
|
|
class A:
|
|
def __init_subclass__(cls):
|
|
raise RuntimeError
|
|
|
|
with self.assertRaises(RuntimeError):
|
|
class B(A):
|
|
pass
|
|
|
|
def test_init_subclass_wrong(self):
|
|
class A:
|
|
def __init_subclass__(cls, whatever):
|
|
pass
|
|
|
|
with self.assertRaises(TypeError):
|
|
class B(A):
|
|
pass
|
|
|
|
def test_init_subclass_skipped(self):
|
|
class BaseWithInit:
|
|
def __init_subclass__(cls, **kwargs):
|
|
super().__init_subclass__(**kwargs)
|
|
cls.initialized = cls
|
|
|
|
class BaseWithoutInit(BaseWithInit):
|
|
pass
|
|
|
|
class A(BaseWithoutInit):
|
|
pass
|
|
|
|
self.assertIs(A.initialized, A)
|
|
self.assertIs(BaseWithoutInit.initialized, BaseWithoutInit)
|
|
|
|
def test_init_subclass_diamond(self):
|
|
class Base:
|
|
def __init_subclass__(cls, **kwargs):
|
|
super().__init_subclass__(**kwargs)
|
|
cls.calls = []
|
|
|
|
class Left(Base):
|
|
pass
|
|
|
|
class Middle:
|
|
def __init_subclass__(cls, middle, **kwargs):
|
|
super().__init_subclass__(**kwargs)
|
|
cls.calls += [middle]
|
|
|
|
class Right(Base):
|
|
def __init_subclass__(cls, right="right", **kwargs):
|
|
super().__init_subclass__(**kwargs)
|
|
cls.calls += [right]
|
|
|
|
class A(Left, Middle, Right, middle="middle"):
|
|
pass
|
|
|
|
self.assertEqual(A.calls, ["right", "middle"])
|
|
self.assertEqual(Left.calls, [])
|
|
self.assertEqual(Right.calls, [])
|
|
|
|
def test_set_name(self):
|
|
class Descriptor:
|
|
def __set_name__(self, owner, name):
|
|
self.owner = owner
|
|
self.name = name
|
|
|
|
class A:
|
|
d = Descriptor()
|
|
|
|
self.assertEqual(A.d.name, "d")
|
|
self.assertIs(A.d.owner, A)
|
|
|
|
def test_set_name_metaclass(self):
|
|
class Meta(type):
|
|
def __new__(cls, name, bases, ns):
|
|
ret = super().__new__(cls, name, bases, ns)
|
|
self.assertEqual(ret.d.name, "d")
|
|
self.assertIs(ret.d.owner, ret)
|
|
return 0
|
|
|
|
class Descriptor:
|
|
def __set_name__(self, owner, name):
|
|
self.owner = owner
|
|
self.name = name
|
|
|
|
class A(metaclass=Meta):
|
|
d = Descriptor()
|
|
self.assertEqual(A, 0)
|
|
|
|
def test_set_name_error(self):
|
|
class Descriptor:
|
|
def __set_name__(self, owner, name):
|
|
1/0
|
|
|
|
with self.assertRaises(RuntimeError) as cm:
|
|
class NotGoingToWork:
|
|
attr = Descriptor()
|
|
|
|
exc = cm.exception
|
|
self.assertRegex(str(exc), r'\bNotGoingToWork\b')
|
|
self.assertRegex(str(exc), r'\battr\b')
|
|
self.assertRegex(str(exc), r'\bDescriptor\b')
|
|
self.assertIsInstance(exc.__cause__, ZeroDivisionError)
|
|
|
|
def test_set_name_wrong(self):
|
|
class Descriptor:
|
|
def __set_name__(self):
|
|
pass
|
|
|
|
with self.assertRaises(RuntimeError) as cm:
|
|
class NotGoingToWork:
|
|
attr = Descriptor()
|
|
|
|
exc = cm.exception
|
|
self.assertRegex(str(exc), r'\bNotGoingToWork\b')
|
|
self.assertRegex(str(exc), r'\battr\b')
|
|
self.assertRegex(str(exc), r'\bDescriptor\b')
|
|
self.assertIsInstance(exc.__cause__, TypeError)
|
|
|
|
def test_set_name_lookup(self):
|
|
resolved = []
|
|
class NonDescriptor:
|
|
def __getattr__(self, name):
|
|
resolved.append(name)
|
|
|
|
class A:
|
|
d = NonDescriptor()
|
|
|
|
self.assertNotIn('__set_name__', resolved,
|
|
'__set_name__ is looked up in instance dict')
|
|
|
|
def test_set_name_init_subclass(self):
|
|
class Descriptor:
|
|
def __set_name__(self, owner, name):
|
|
self.owner = owner
|
|
self.name = name
|
|
|
|
class Meta(type):
|
|
def __new__(cls, name, bases, ns):
|
|
self = super().__new__(cls, name, bases, ns)
|
|
self.meta_owner = self.owner
|
|
self.meta_name = self.name
|
|
return self
|
|
|
|
class A:
|
|
def __init_subclass__(cls):
|
|
cls.owner = cls.d.owner
|
|
cls.name = cls.d.name
|
|
|
|
class B(A, metaclass=Meta):
|
|
d = Descriptor()
|
|
|
|
self.assertIs(B.owner, B)
|
|
self.assertEqual(B.name, 'd')
|
|
self.assertIs(B.meta_owner, B)
|
|
self.assertEqual(B.name, 'd')
|
|
|
|
def test_set_name_modifying_dict(self):
|
|
notified = []
|
|
class Descriptor:
|
|
def __set_name__(self, owner, name):
|
|
setattr(owner, name + 'x', None)
|
|
notified.append(name)
|
|
|
|
class A:
|
|
a = Descriptor()
|
|
b = Descriptor()
|
|
c = Descriptor()
|
|
d = Descriptor()
|
|
e = Descriptor()
|
|
|
|
self.assertCountEqual(notified, ['a', 'b', 'c', 'd', 'e'])
|
|
|
|
def test_errors(self):
|
|
class MyMeta(type):
|
|
pass
|
|
|
|
with self.assertRaises(TypeError):
|
|
class MyClass(metaclass=MyMeta, otherarg=1):
|
|
pass
|
|
|
|
with self.assertRaises(TypeError):
|
|
types.new_class("MyClass", (object,),
|
|
dict(metaclass=MyMeta, otherarg=1))
|
|
types.prepare_class("MyClass", (object,),
|
|
dict(metaclass=MyMeta, otherarg=1))
|
|
|
|
class MyMeta(type):
|
|
def __init__(self, name, bases, namespace, otherarg):
|
|
super().__init__(name, bases, namespace)
|
|
|
|
with self.assertRaises(TypeError):
|
|
class MyClass(metaclass=MyMeta, otherarg=1):
|
|
pass
|
|
|
|
class MyMeta(type):
|
|
def __new__(cls, name, bases, namespace, otherarg):
|
|
return super().__new__(cls, name, bases, namespace)
|
|
|
|
def __init__(self, name, bases, namespace, otherarg):
|
|
super().__init__(name, bases, namespace)
|
|
self.otherarg = otherarg
|
|
|
|
class MyClass(metaclass=MyMeta, otherarg=1):
|
|
pass
|
|
|
|
self.assertEqual(MyClass.otherarg, 1)
|
|
|
|
def test_errors_changed_pep487(self):
|
|
# These tests failed before Python 3.6, PEP 487
|
|
class MyMeta(type):
|
|
def __new__(cls, name, bases, namespace):
|
|
return super().__new__(cls, name=name, bases=bases,
|
|
dict=namespace)
|
|
|
|
with self.assertRaises(TypeError):
|
|
class MyClass(metaclass=MyMeta):
|
|
pass
|
|
|
|
class MyMeta(type):
|
|
def __new__(cls, name, bases, namespace, otherarg):
|
|
self = super().__new__(cls, name, bases, namespace)
|
|
self.otherarg = otherarg
|
|
return self
|
|
|
|
class MyClass(metaclass=MyMeta, otherarg=1):
|
|
pass
|
|
|
|
self.assertEqual(MyClass.otherarg, 1)
|
|
|
|
def test_type(self):
|
|
t = type('NewClass', (object,), {})
|
|
self.assertIsInstance(t, type)
|
|
self.assertEqual(t.__name__, 'NewClass')
|
|
|
|
with self.assertRaises(TypeError):
|
|
type(name='NewClass', bases=(object,), dict={})
|
|
|
|
|
|
if __name__ == "__main__":
|
|
unittest.main()
|